1. Field of the Invention
This invention relates generally to a cap inspection apparatus and more particularly to a cap inspection apparatus which detects defectively capped bottles.
2. Description of the Prior Art
With the advent of machinery capable to fill and cap bottles, a need for an inspection system for detecting defective bottles simultaneously arose.
Machines were also developed to automatically cap filled bottles. Inspection systems for detecting defective caps were developed.
One inspection system for detecting defective caps is disclosed in U.S. Pat. No. 3,499,314, issued to Roberts et al on Mar. 10, 1970. Roberts et al discloses an apparatus for testing covers when covers are placed into a cell. The cell has an upper half and lower half. A high pressured gas stream passes into the lower half of the cell. If the cap is defective, gas will seep into the upper half of the cell and be detected by a transducer in communication with the upper half.
Often, however, the cap itself may not be defective but may merely be defectively placed on the bottle when it is not properly capped with the cap. It is, therefore, desirable to an inspection system which inspects caps after they are capped onto a bottle.
U.S. Pat. No. 3,847,014, issued to Mistarz on Nov. 12, 1974, discloses an enclosure leak tester for detecting leaky caps. A piston is extended downwardly to deform a cap. A bore passing through the piston is connected to a backing pump. The open end of the bore abuts the top of the cap. As the piston pushes down on the cap, rollers flex the upper side walls of the container. The piston then extends a bit upwardly. If the cap is conforming, a resilient cap will follow the piston upwardly and maintain the vacuum within the bore. If the cap is a leaker, the cap will disengage the bore. The device is limited to testing only resilient caps that are capped on deformable containers.